1. Field of the Invention
The present invention relates to an illumination adjusting circuit, and more especially to a digital illumination adjusting circuit which can adjust the output to a power level of an alternating load via a digital setting manner.
2. Description of the Prior Art
Traditional illumination adjusting circuit controls the illumination level of a light or bulb by a TRIAC cooperating with a conductive angle controlling circuit and a variable resistor. However, this traditional illumination adjusting circuit can only adjust the illumination of the light while not able to perform varieties of illumination pattern setting and programming. Therefore, this traditional illumination adjusting circuit can only be applied in illumination adjusting function, neither applied for other fields nor combined with other digital circuit for more flexible use.
Moreover, the adjusting of the conductive angle of the traditional illumination adjusting circuit is achieved by adjusting a variable resistor. Since the adjusting work is done manually, the precision of the adjusting is not satisfactory and the user can only estimate by eye vision for the output power level. This may be satisfactory in a normal illumination adjusting, but it can not meet the more precise illumination adjusting or cooperate with other digital circuit to achieve other purposes.
It is requisite and valuable to design an illumination adjusting circuit which can be optionally set by the user's intention with very high precision.